As shots ring out east of Donetsk, the leaders of Russia and Ukraine met for talks in Minsk, agreeing on the need to "de-escalate" and free hostages.

But the president of Belarus, who hosted the talks, says fundamental differences remain.

Starting with a handshake, the talks were aimed at defusing a separatist war that has heightened tensions between Russia and NATO and has prompted the U.S. and the EU to slap sanctions on Russia.

President Vladimir Putin says Russia will respect a country's sovereignty, but not at their own expense.

"Russia has always respected and will respect the sovereign choice of any country in organizing its political life and forming economic and military units, but we hope it will not damage other members of the international community and will happen not at our expense," Putin said.

"We should do everything to stop supplies of military hardware and weapons to the rebels, because we are deeply convinced that effective border controls are only possible with participation of the OSCE," according to Poroshenko.

Though talks have made some headway, eastern Ukraine is still a battleground. A U.N. report obtained by Reuters claims at least 2,000 people have died in the conflict so far.